What is Disodium Sulphide Hydrate?
Disodium sulphide exists most commonly in the nonahydrate form, a yellow solid which is very hygroscopic. It readily dissolves in water to form a strong alkaline solution. When exposed to air the salt produces a foul smelling gas, hydrogen sulphide, often referred to as rotten eggs. Disodium sulphide is commercially produced by the reduction of sodium sulphate with carbon at high temperatures.
- Synonyms: sodium sulfide; sodium sulphide; disodium sulphide; sulfure de sodium; sulfuro de sodio; Natriumsulfid; natriumsulfide;
- Cas No: 1313–84–4
- EINECS: 215–211–5
- Formula: Na2S 9H2O
- Molar mass: 240.18 g/mol
- Appearance: Yellow flakes
- Density: 1.43 g/cm3
- Melting point: 50C
- Boiling point: 920C
- Autoignition temperature: >480C
- Solubility: 18.6 g/100 mL (20 oC)
- Explosive limits: Lower 4.3% Upper 45%
- Vapor Pressure (mmHg): 750.062 @ 145–175 C
Disodium sulphide is easily soluble in cold water & hot water. Very slightly soluble in methanol. Insoluble in diethyl ether, n-octanol.
Uses of sodium sulphide
Disodium sulphide is primarily used in pulp and paper industry in the kraft process.It is used in water treatment as an oxygen scavenger agent, in the photographic industry to protect developer solutions from oxidation, in textile industry as a bleaching, as a desulfurising and as a dechlorinating agent and in leather trade for the sulfitisation of tanning extracts and as a depilatory for leather hides. It is used in chemical manufacturing as a sulfonation and sulfomethylation agent. It is used in the production of rubber chemicals, sulfur dyes and other chemical compounds. It is used in other applications including ore flotation, oil recovery, food preservative, making dyes, and detergent. Disodium sulphide is used in the preparation of sodium thiosulphate.
Health & Safety
Classification: Corrosive, Dangerous for the environment
Risk phrases: R31 Contact with acids liberates toxic gas. R34 Causes burns. R50 Very toxic to aquatic organisms.
Safety phrases: S1/2 Keep locked up and out of reach of children. S26 In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S45 In case of accident or if you feel unwell, seek medical advice immediately (show the label where possible). S61 Avoid release to the environment. Refer to special instructions/Safety data sheets.
For full details see MSDS for Disodium sulphide